Electric motor brush holder



y 6, 1961 E. K. HANSEN ET AL 2,984,758

ELECTRIC MOTOR BRUSH HOLDER Filed June 1, 1959 INVENTORS EVERETT K. HANSEN ALLEN J. PETERSEN ATQORNEY 1 United States Patent 2,984,758 ELECTRIC MOTOR BRUSH HOLDER Everett K. Hansen and Allen J. Petersen, Racine, Wis., assignors to Rae Motor Corporation, .Racine, 'Wis., a corporation of Wisconsin Filed June 1, 1959, Ser. No. 817,207

4 Claims. (Cl. 310-239) This invention relates to an electric motor brush holder, and more particularly, it relates to a brush holder consisting of both the motor housing and the separate holder parts.

It is an object of this invention to provide a brush holder which in part is made integral with the motor housing by means of die casting .said part directly with the housing. In achieving this object, there is eliminated the usual requirement of spot-welding or otherwise fastening the brush holder part which is connected to the housing, since the holder is now made integral with the housing.

Another object of this invention is to provide a brush holder which is more easily and accurately aligned with respect to the motor housing and thus the required alignment and .contact of brush with commutator is better achieved. This particular object is accomplished by the die casting mentioned, and, because of die casting, the part of the holder attached to the housing is properly aligned with the housing, and further, the separable part of the holder is improved over the parts heretofore known, so that here also better alignment is achieved.

Still another object of this invention is to provide a brush holder which requires less labor in manufacture and assembly and thus is less expensive, and still the aforementioned objects are accomplished.

Still a further object is to provide a brush holder which is readily adaptable to variations in brush sizes while still providing a holder which is automatically and accurately aligned in the motor housing.

These and other objects and advantages will become apparent upon reading the following description in conjunction with the accompanying drawings wherein:

Fig. 1 is a top plan view of a motor housing with one brush holder in position thereon.

Fig. 2 is a sectional view taken along the line 22 of Fig. 1.

Fig. 3 is a top plan view piece shown in Figs. 1 and 2.

The same reference numerals refer to the same parts throughout the several views.

The drawings show a motor housing or end cap which is of a cup shape and of course it will be understood that the remainder of the motor will suitably attach to the cap, and the motor parts will be disposed therein in the well-known manner. In this invention it is significant that the housing 10 is made of a die casting process so that a pair of shoulders or raised portions 11 is located on each diametrically opposite side of the housing 10 and is die cast with the housing 10 to be an integral part thereof. In this manner, the shoulders 11 are properly and accurately disposed within the housing 10 to be directed toward the center thereof and aligned with the central portion of the housing for a purpose hereinafter mentioned. Also as shown in the drawings, arcuate portions 12 are die cast in and with the housing 10 and shoulders 11 so that, as mentioned, the parts 10, 11 and 12 are all made in one die cast unit to that the top or of the holder insulation 2,984,758 Patented May 16, 1 961 ice upper surfaces 13 of the shoulders 11 are disposed above the surface 14 which is intermediate the shoulders 11. Also, each shoulder 11 has prongs or clamps 16 which project above the surface 13 as clearly shown in Fig. 2.

Figs. 1 and 3, particularly, show the holder piece 17, which can be made of the usual electrical insulation material, to be provided with four corner notches or recesses 18 which receive the prongs 16 as shown in the assembly views. Also of course, the lower surface of the piece 17' rests upon the shoulder upper surfaces 13 so that the piece 17 is securely and accurately disposed with respect to the die cast shoulders 11 and thus the piece 17 is automatically and properly aligned in the housing 10. Of course a slight crimping or bending or swaging of the prongs 16 will secure the piece 17 to the housing 10 as desired. A brush metal casing 19 is attached to the insulation piece 17 by means of the casing tabs 21 passing through the slots 22 in the piece 17. Here also the tabs or prongs 21 are crimped or bent inwardly to secure the rectangular casing 19' to the piece 17 in the usual manner. Particularly Fig. 2 shows that the 'holder casing 19 is aligned with the opening 23 in the housing 10, and this opening 23 of course provides a mounting and access opening to the electrical brush (not shown) which would be disposed within the casing 19 in the usual manner. At this time it should also be noted, as shown in Fig- 3, that the piece 17 is provided with two other slots or slits 24 and these are spaced further apart than the spacing between the slits 22 and thus the slits,24 will accommodate a wider casing 19 so that the size of the brush holder in the assembly is readily and easily variable for different specifications required. Of course it will further be understood that the height ofthe casing 19 can be varied and in these variations, four different sizes of casings 19, and therefore four different sizes of brushes can be employed because of the two sets of slits 22 and 24, and with the piece 17 being readily able to accommodate these two sets of slits as the piece 17 is anchored through its corner notches 18 which do not interefere with the provision and location of the slits 22 and 24.

Another important feature of this arrangement is that the tabs 21 of the casings 19, which is normally a metal casing, are spaced from the end wall 14 in the motor housing 10 and thus there is no problem of shorting the motor through the brushes and the casings l9 and the housing 10. This spacing is of course provided by the raised shoulders 11 so that, in addition to the shoulders 11 automatically aligning the insulation piece 17, it can be said that the shoulders 11 provide the required spacing of the tabs 21 from the housing 10. Also, a minimum of labor is required in the manufacture of the motor and particularly in the assembly of the brush holders in the position shown, as the raised portions or shoulders 11 are already in position in the die cast housing 10 and there need be only unskilled labor in inserting the insulation piece 17 with the casing 19 into the position shown and then slightly crimping or bending the prongs 16, or otherwise upsetting them inwardly toward each other, to secure the piece 17 in position.

In this manner, a brush holder section consisting of the raised shoulder 11 with prongs 16 and including the insulation piece 17 with casing 19, is provided for the objects and advantages mentioned at the outset. In the manner further mentioned, the holder section is an improvement over those heretofore known, including those which have pronged pieces spot welded to the motor housing and two prongs projecting thereon, and yet it has the cost and labor advantages mentioned.

While a specific form of this invention has been shown and described, it should be obvious that certain deviations therefrom could be effected, and the invention should,

therefore, be limited onlyby the scope of the appended claims.

What is claimed is:

1. A brush holder for an electric motor, comprising a cup-shaped motor housing including two access openings on diametrically opposite sides thereof for insertion and removal of an electrical brush with respect to the interior of said housing, a pair of shoulders integral with said housing on the end wall thereof and being disposed therein oriented with each one of said access openings and each including an upper surface spaced from said end wall of said housing, two prongs integral with and spaced apart on each of said surfaces and projecting thereabove, an insulation piece disposed on each pair of said'surfaces and spanning each said pair of shoulders and having four notched corners respectively receiving said prongs for alignment and attachment of said piece with respect to said housing, and a brush casing attached to the upper surface of said piece by including prongs extended through said piece and into the space between said piece and said housing wall for aligning with said access openings.

2. A brush holder for an electric motor, comprising a die cast motor housing including an end wall, a pair of shoulders die cast integral with said housing and being disposed therein oriented with the central axis of said housing and each including an upper surface spaced from said end wall of said housing and disposed transverse to said axis, an insulation piece disposed on said surfaces and spanning said shoulders and having four notched corners, two prongs spaced apart on each of said surfaces and extending therefrom through respective ones of said inotched corners and extending beyond said insulation piece in a free end for alignment and attachment of said piece with respect to said housing, and a brush casing attached to the upper surface of said piece by including prongs extended through said piece into the space between said piece and said housing wall.

3. A brush holder for an electric motor, comprising a motor housing, a projection section within said housing and including two spaced-apart surfaces defining a space with the wall of said housing, two spaced-apart prongs on each of said surfaces and extending therefrom in the direction away from said wall, an insulation piece disposed on said surfaces and spanning said space and having four recesses therein for receiving said prongs, said piece having four spaced-apart slots therein in the projected area of said space and with said slots being disposed to present two pairs of slots with the slots in each of said pairs being staggered across said piece with respect to the direction of the shortest distance between said surfaces, and a brush casing of a selected width attached to said piece by ineluding two prongs of a selected spacing sufficient for extending through a selected one of said pairs of said slots and with the ends of the latter said prongs being disposed in said space away from said wall of said housing.

4. A die cast electric motor brush holder section comprising a one-piece housing including a recessed portion flanked by upstanding prongs cast to be integral with said housing and extending away from said recessed portion and terminating in free ends, an insulation piece having recesses for receiving said upstanding prOngs and with said prongs extending beyond the thickness of said piece; for attaching said piece to said housing when said free ends are upset toward said piece, a brush casing including projections, said insulation piece having slots for receiving said projections in said recessed portion for securing said casing to said piece and with said projections being spaced from said housing.

References Cited in the file of this patent UNITED STATES PATENTS 

